later this very hour, president obama and the city of boston as well as this nation will mark a moment of silence at 2:50 eastern time. the exact moment the first bomb exploded. bells will ring afterward. massachusetts governor deval patrick and thomas menino will be on hand of the neighborhood of 8-year-old vimd martin richard. also today the first funeral was held for the bombing victims. the capacity crowd mourned. krystle campbell, the 29-year-old at the finish line clearing on a friend. and later this evening, boston university will hold a memorial service for lu lingzi, the 23-year-old graduate, the student from china also killed in the blast. meanwhile as crews clean up the crime scene today, new questions about how the fbi interrogated tamerlan tsarnaev before the attacks. >> why didn't the fbi follow up on that? you combine the first interrogation, the first examination plus the subsequent act. when somebody is brought to your attention, you investigate and find nothing and then he carries out murders, you wonder, didn't you miss something in the investigation? >> and today, o